Remote hanger



Feb. 11, 1969 E. w. KEARNS ET AL 3,426,848

REMOTE HANGER Filed Dec. 5, 1966 Sheet of 2 Feb. 11, 1969 Filed Dec;

E. w. KEARNS ET AL REMOTE HANGER Sheet 2 of 2 E. W ffea/vw Jfe a/ie/r 7.(of/00 INVENTORS United States Patent 3,426,848 REMOTE HANGER Edwin W.Kearns, Houston, and Stephen T. Cutlip,

Bellaire, Tex., assignors to Rockwell Manufacturing Company, Houston,Tex., a corporation of Pennsylvania Filed Dec. 5, 1966, Ser. No. 599,116US. Cl. 166-214 Int. Cl. E2111 23/00, 33/03; F16! 37/18 Claims ABSTRACTOF THE DISCLGSURE The specification discloses a combination of wellheadwith a hanger received within the wellhead for supporting a well pipe.The hanger disclosed is supported on a shoulder and has resilient armswhich engage an annular groove in the bore of the wellhead and therebyhold the hanger down against any forces which may tend to push thehanger upwardly in the wellhead. A plug element is used to hold the armsin the groove.

vised to hold the casing or tubing down. Most of these methods do so byholding down the hanger to which the casing or tubing string isattached. Many of these methods require external means such as thelockscrew. Lockscrews are especially undesirable in underwater wellheadswhere they are not easily operable and are exposed to the seaenvironment.

The subject invention is a pipe hanger and a completely internal holddown means which are remotely installed in a wellhead. The hold downmeans comprises cantilevered springs integral with the hanger body whichallow the hanger to pass through a valve of the same nominal size as thetubing or casing supported by the hanger. In its seated position withinthe wellhead, the hanger is locked down by an internal sleeve plug whichholds a portion of the cantilevered springs in a groove within thewellhead. The hanger and attached pipe string may be easily removed byremoving the plug.

It is, therefore, an object of the invention to provide a pipe hangerand completely internal hold down means which may be easily and remotelyinstalled in a wellhead.

Another object is to provide a pipe hanger and internal hold down meanswhich may be passed through a valve of the same nominal size as the pipestring supported by the hanger.

Still another object is to provide a pipe hanger and internal hold downmeans which may be easily retrieved from a remote wellhead.

Further objects and advantages will become apparent from the followingdrawings and description wherein:

FIGURE 1 is an elevation in partial section showing the inventionemployed in a tubing head;

FIGURE 2 is an elevational view in section of the hanger of theinvention;

FIGURE 3 is an elevational view in section of the sleeve means used tolock the hanger of FIGURE 2 in place within the wellhead;

FIGURE 4 is an elevational view in section of the See tool used to runand pull the sleeve of FIGURE 3; and

FIGURE 5 is an elevational view in partial section showing the hanger ofFIGURE 2 being lowered into its support position.

Referring first to FIGURE 1, there is shown a tubing string 4, supportedin a tubing head 2 by hanger 6. Hanger 6 rests on an upwardly facingfrusto-conical shoulder on the interior wall of tubing head 2. Hanger 6has a plurality of spring fingers 12 integral with the body of hanger 6extending upwardly therefrom. Spring fingers 12 have small lugs 14 whichrest within a groove 16 machined on the interior of tubing head 2. Athreaded sleeve 10 is connected to hanger 6 so that its exterior liesagainst the interior faces of spring fingers 12. Thus, spring fingers 12are prevented from disengaging groove 16 and hold down tubing string 4against excessive reservoir pressures.

Attached above tubing head 2 is production valve 18. As will be seen,hanger 6 may be lowered through valve 18 if it is of the same nominalsize as tubing 4. Also attached to tubing head 2 is valve 20 whichallows production through annulus 22. Although a single tubing stringwellhead is shown, the hanger apparatus of the invention may be usedwith multiple tubing wells. In fact, it is very desirable in multipletubing wells since no external hold down means is required and spacerequirements are relatively small.

Now referring to FIGURE 2, hanger 6 and spring fingers 12 will bedescribed in detail. Hanger 6 is generally cylindrical in shape. Asmaller diameter lower portion 30 is joined to the larger diametermiddle portion 32 by a downwardly facing frusto-conical shoulder 34which cooperates with shoulder 8 within tubing head 2 to provide supportmeans. (See FIGURE 1.) On the exterior of middle portion 32 two groovesare provided for O ring seals 34'. The exterior of lower portion 30 isprovided with connection means 36 such as threads to receive a pipestring for suspension. The interior of middle portion 32 is providedwith threaded connection means 38 to receive a pipe for lowering hanger6 into a well or for inserting sleeve 10 as shown in FIGURE 1.

The upper portion of hanger 6 comprises spring fingers 12. Springfingers 12 are conveniently formed by machining the upper portion ofhanger 6 to the same outside diameter as middle portion 32, except forthe extreme upper end which is machined with intersecting frustoconicalsurfaces 40 and 42. These bevelled surfaces allow the lugs to slide overobstructions and smaller diameter bores when the hanger is movedupwardly or downwardly in the wellhead equipment. The inside diameter ofthe upper portion is then machined to a greater dimension than the restof the interior of hanger 6. Then longitudinal slots 44 are cut from theupper end of hanger 6 to its middle portion 32. Thus, cantilever actingspring fingers 12 are formed with lugs 14 at the free end therof. Theends of spring fingers 12 may be forced toward the axis of hanger 6until lugs 14 lie completely within the outside diameter of middleportion 32. When such forces are removed, fingers 12 return to theposition shown in FIGURE 2.

Referring also now to FIGURE 3, sleeve 10 will be described. Sleeve 10is a tubular body with a reduced diameter lower exterior 50 which isthreaded to fit threads 38 of hanger 6. The upper exterior 54 of sleeve10 has a diameter slightly less than the inside diameter of hanger 6 atspring fingers 12. Thus, if sleeve 10 is connected to hanger 6 bythreaded connection 38 and 50, upper exterior 52 will prevent fingers 12from being forced inwardly. The upper interior of sleeve 10 is providedwith a groove 54 formed by intersecting frusto-conical surfaces. Slots56 are machined at degree intervals on the upper edge of sleeve 10.Slots 56 and groove 54 are for engage- 3 ment of a running and pullingtool 60 shown in FIG- URE 4.

The lower end of running and pulling tool 60 is a cylindrical extension62 with a diameter slightly less than the inside diameter of sleeve 10.Spring loaded plungers or detents 63 are mounted in a hole drilled inextension 62 perpendicular to its axis. Plungers 63 are biased topartially project out of entension 62. Welded to extension 62 iscylindrical hub 64 which has two keys 66 machined at its base. Keys 66and plungers 63 are so positioned that they may engage slots 56 andgroove 54 respectively on sleeve 10. At the upper end of running andpulling tool 60, collar 68 is provided which is threaded on its interior70 to receive a running pipe string for lowering into the well. Setscrews 72 assure that tool 60 will not be accidentally separated fromthe running string. Collar 68 is attached to hub 64 by a joint of pipe74.

Referring now to FIGURE 5, the installation of hanger 6 will beexplained. Hanger 6 is first connected to tubing string 4. Then a stringof tubing 3 is screwed into the threaded connection on the interior ofhanger 6. Hanger 6 and tubing string 4 are then lowered into the wellbore until shoulder 34 contacts support shoulder 8 within tubing head 2.As hanger 6 is lowered into the well bore spring fingers 12 may beforced inwardly allowing hanger 6 to pass through valve 18 or any borewhich would allow the passage of the middle portion 32. When hanger 6reaches its support position at shoulder 8, groove 16 receives lugs 14of spring fingers 12 allowing the fingers to return to their normalposition. Drill pipe 3 is then disconnected and removed from the wellbore.

At this point hanger 6 is fully supporting tubing string 4. However,nothing is preventing the string from moving upwardly if excessivebottom hole pressures arises since fingers 12 may spring inwardly due tothe sloped surfaces of groove 16 and lugs 14. To remedy this situationsleeve 10 is attached to running and pulling tool 60 by keys 66 andplungers 63 engaging slots 56 and groove 54. (See FIGURES 3 and 4.) Tool60 and sleeve 10 are then lowered on a pipe string until sleeve 10 iswithin hanger 6. Tool 60 and consequently sleeve 10 are then rotateduntil sleeve 10 has fully engaged the threaded connection on theinterior of hanger 6. Tool 60 is now removed from the well bore bysimply pulling it upwardly. The apparatus now appears as shown inFIGURE 1. As can be seen, the outside diameter of sleeve 10 is onlyslightly less than the inside diameter of hanger 6 at the inner faces offingers 12. Thus, finger lugs 14 are prevented from being forcedinwardly of groove 16 and hanger 6 and tubing string 4 are positivelyheld down against excessive bottom hole pressures.

The present invention also allows hanger 6 to be retrieved along withtubing 4. To do this, tool 60 is lowered into engagement with sleeve 10.Sleeve 10 is then unscrewed from hanger 6 and removed from the well. Apipe string is then lowered into the well and rotated to engage thethreaded connection on the interior of hanger 6. Hanger 6 and tubingstring 4 are then pulled upwardly. Finger springs 12 are forced inwardlydue to the cooperating fnusto conical surfaces of lugs 14 and groove 16thereby releasing hanger 6 for upward travel.

Thus, it can be seen from the preceding description that effective holddown of a pipe string has been attained by completely internal means.The apparatus used may be easily installed by remote control and maylikewise be easily removed.

Although only a single preferred embodiment of the invention has beendescribed many modifications thereof can be made by one skilled in theart Without departing from the spirit of the invention and it isintended that the invention be limited only by the scope of thefollowing claims.

We claim:

1. Internal means for holding down a pipe hanger and its supported pipestring within a wellhead comprising:

spring fingers extending upwardly from said hanger around its upperperiphery, said fingers being longitudinal strips separated by slotsopened at the upper end to allow said fingers to be forced inwardly attheir upper ends, lugs projecting radially outward from the upper endsof said fingers engageable with an annular groove in said wellhead whensaid fingers are in a non-deflected position; and

sleeve means remotely engageable with said pipe hanger to preventdisengagement of said hanger from said wellhead by maintaining saidnon-deflected position of said fingers. 2. The combination of claim 1wherein the inner surfaces of said finger means substantially define aportion of a cylinder in said non-deflected position and the outersurface of said sleeve means is a cylindrical surface in close proximityto said fingers throughout their length.

3. The combination of claim 1 wherein said sleeve means and said hangerare connected by connection means preventing relative axial movementtherebetween.

4. Internal means for holding down a pipe hanger and its supported pipestring within a wellhead comprising:

cantilevered spring fingers extending upwardly from said pipe hanger,the outer faces of which define a portion of a cylinder of a diameterslightly less than the bore of said wellhead, the inner faces of whichdefine a portion of a smaller diameter cylinder, the extreme upper endof said fingers being provided with outwardly projecting lugs engageablewith annular groove means on the interior of said wellhead when saidfingers are in a non-deflected position; and

tubular sleeve means remotely insertable within said hanger means havingthreads thereon engageable with threads on the interior of said hangerto prevent relative axial movement therdbetween, the upper exterior ofsaid sleeve means comprising a cylindrical surface of a diameterslightly less than the diameter of said finger inner faces and adjacentto said fingers throughout their length to prevent deflection thereof.

5. The combination of claim 4 wherein said lugs are provided withupwardly facing and downwardly facing inwardly converging surfaces toinwardly deflect said fingers when said sleeve means is removed and saidhanger is moved upwardly or downwardly through diameters less than thediameter of said wellhead annular groove means.

References Cited UNITED STATES PATENTS 3,292,717 12/1966 Hall et al.166-217 3,339,944 9/1967 Poague 285-319 3,361,212 1/1968 Page 166224JAMES A. LEPPINK, Primary Examiner.

U.S. Cl. X.R.

